On some systems, you may experience problems using the backspace or delete keys. This tip discusses the causes and solutions. Generally, these problems arise on Unix-based systems because of the wide variety of hardware and software involved.

Checking for bad mappings

Your backspace key may be broken due to a bad mapping which has been loaded into Vim. This may be unintentional; Vim sees CTRL-H as a backspace (because CTRL-H is the ASCII code for a backspace), so you also cannot map anything to that. You can check if there are any mappings set, and where they came from, like this: